Michio Akima
Toho University
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The American Journal of Surgical Pathology | 1997
Nobuyuki Hiruta; Noriaki Kameda; Takahiro Tokudome; Kazuaki Tsuchiya; Hiroko Nonaka; Tsutomu Hatori; Michio Akima; Myota Miura
This report concerns a malignant glomus tumor, a rare soft tissue tumor that was examined immunohistochemically and ultrastructurally. It occurred in a 44-year-old male patient who had suffered from dull pain and stiffness in the right thigh for 10 months. Radiographic examination revealed a well-defined osteolytic lesion in the diaphysis of the right femur. Hypervascularity of the tumor was observed angiographically. Computed tomographic and magnetic resonance examinations showed an intramuscular mass invading the marrow space of the femur. Wide resection was performed after open biopsy. Histologically, round to polygonal tumor cells revealed a uniform appearance of round to ovoid nuclei with single large nucleoli and slightly eosinophilic cytoplasm, forming solid sheets of cells interrupted by vessels of varying size. A few mitotic figures and vascular invasion were observed. Immunohistochemically, vimentin and alpha-smooth muscle actin were stained intensely, and muscle actin was positive for tumor cells of the perivascular area. Tumor cells were negative for desmin, factor VIII-related antigen, S-100 protein, neurofilament, cytokeratin, and epithelial membrane antigen. Ultrastructurally, tumor cells were characterized by many cytoplasmic processes, pinocytotic vesicles, plasmalemmal dense plaques, and scattered microfilaments in the cytoplasm. Few cell junctions and focal basement membrane-like structures were observed. No recurrence or metastasis was noted 57 months after operation. This case was considered to be a malignant glomus tumor, that is, a glomangiosarcoma arising de novo.
Neuropathology | 2003
Hiroko Nonaka; Michio Akima; Tsutomu Hatori; Tadashi Nagayama; Zean Zhang; Fumie Ihara
The vascular architecture of the human cerebral deep white matter was studied using soft X‐ray and diaphanized specimens, achieved by intra‐arterial injection of barium and vascular stain respectively, and also by electron microscopic examination of the corrosion cast of arteries in normal adult brains. The deep white matter arteries passed through the cerebral cortex with a few branches to the cortex and ran straight through the white matter. The arteries concentrated ventriculopetally to the white matter around the lateral ventricle. Anastomoses were noted around the ventricular wall at the terminals of the deep white matter arteries. No centrifugal branches irrigating the periventricular white matter from the lenticulo‐striate arteries were observed in the present study. The presence of anastomoses among the terminal branches of deep white matter arteries protects against ischemic change or infarction in this area from an occlusion of a single deep white matter artery. This may lead to development of terminal zone infarction from ischemia or vascular diseases, affecting multiple deep white matter arteries. The subcortical and deep white matter arteries had thick adventitial sheaths and large adventitial spaces in the white matter but not in the cortex. The presence or absence of the adventitial space is regarded as another characteristic difference between the arteries in the white matter and cortex. This difference may influence pathological changes in vascular lesions in these respective areas.
Neuropathology | 2003
Hiroko Nonaka; Michio Akima; Tadashi Nagayama; Tsutomu Hatori; Zean Zhang; Fumie Ihara
In the present study, the human cerebral meninges were rich in blood vessels, but no capillaries were noted. The meningeal arteries ran over the veins where they crossed. Several arterial anastomoses existed on the cortical surface. The meningeal arteries were classified into four parts; the conducting artery approximately 700 µm in diameter, distributing artery approximately 200 µm in diameter, precortical artery approximately 60 µm in diameter and cortical artery approximately 30–40 µm in diameter. A single distributing artery supplied the area of approximately 3.5 × 2.0 mm on the brain surface. They further ramified into precortical arteries which stemmed cortical arteries. These precortical arteries had the distributing area of 1 mm2 and this distributing area was the same size as the width of human ocular dominant column of the visual cortex. Constriction, like a sphincter, was observed at the bifurcation of the distributing arteries. The cerebral blood vessels, which regulated the blood flow and reacted to autonomic nerve stimuli, seemed to correspond to the distributing arteries.
Acta Neuropathologica | 1987
Michio Akima; Hiroko Nonaka; Mineyuki Kagesawa; K. Tanaka
SummaryThe arterial structure of the cerebellar cortex was studied by vascular stain and in diaphanized specimens after intra-arterial barium injection. A scanning electron microscope study on the corrosion cast of the arteries was also performed. Arteries distributed in the cerebellar hemisphere are classified into cortical, subcortical, and medullary arteries. The patterns of arterial distribution are similar to those in the cerebral cortex. The cortical arteries are subclassified into superficial, middle, and deep cortical branches. The superficial branches are very fine, forming capillary networks in the molecular layer. The middle cortical branches terminate in the Purkinje cell layer, by dividing into several branches extending parallel to the plane of this layer. These branches connect with capillaries in both the molecular and the granular layers. The deep cortical branches give off some collaterals along the Purkinje cell layer and terminate in the granular layer, by breaking up into capillary networks. The Purkinje cell layer is marked by arterial branches ramified from the middle and deep cortical branches and no particular dense capillary networks are formed in the Purkinje cell layer. The brains of older patients show intertwining of the middle and deep cortical branches, some forming “rope-like” appearance. These patterns are similar to those seen in the cerebral cortex, but they were found, in older people, in the cerebrum.
Pathology International | 2008
Noriaki Kameda; Mineyuki Kagesawa; Nobuyuki Hiruta; Michio Akima; Megumi Ohki; Tsukasa Matsumoto
A 62‐year‐old female with primary leiomyosarcoma of the left femur is reported with a review of 21 cases reported in the literature. The resected specimen showed that the tumor extended from the femoral head to the diaphysis for 13cm in length. The tumor showed mainly intramedullary proliferation, but extraosseous growth was also noted at the great trochanter. Microscopic examination revealed well differentiated leiomyosarcoma characterized by interlacing bundles of fusiform cells with eosinophilic cytoplasm and rod‐shaped hyperchromatic nuclei. PAP stain of actin on the tumor cells was positive. On electron microscopy, microfilament of 6–8 nm in diameter, dense bodies, plnocytotic vesicles, marginal attachment plate, and basal lamina were noted. The patient died with pulmonary metastasis, 1 year and 7 months after the operation. An autopsy showed metastases in the right pelvic cavity and bilateral lungs, and confirmed the primary site to be the left femur.
Neuropathology | 1998
Hiroko Nonaka; Michio Akima; Tadashi Nagayama; Tsutomu Hatori; Zean Zhang
The microvascular architecture of the basal ganglia of human brains was studied on diaphanized specimens after intravascular barium injection and vascular stains. Observation by scanning electron microscope was also performed. The putamen and caudate nucieus showed dense capillary networks. Less dense capillary networks were noted in the capsula interna. The capillary network in the globus pallidus was less dense than that in the striatum but denser than that in the capsula interna. The lenticulostriate arteries ran through the putamen, across the internal capsule and reached the caudate nucleus. Though the arterial branches running within the putamen had many small branches, branching was minimal while crossing the capsula interna and began showing rich ramification again when they reached the caudate nucleus. There were retrograde ramifications in the putamen and caudate nucleus. They appeared to play a significant role in the regulation of blood pressure and are considered to play some role in the occurrence of circulatory disturbances which are prone to involve these structures. The fountain‐like ramifications were seen in the putamen and caudate nucleus, but their function is not clear. In the brains of senile patients, intertwining of the arterial blood vessels was noted in the fountain‐like rami. This structure began to appear in the patients over the age of 50. While the etiology of the intertwining of the arteries remains unknown, its increasing frequency with age supports a hypothesis that this represents a phenomenon correlated with aging or concomitant brain atrophy.
Neuropathology | 1993
Michio Akima
We have examined the microvasculature of the human cerebral cortex, basal ganglia, hippocampus, cerebellar cortex and pons. In this presentation we summarize the results andy on the discuss the relationship between vasculature and the selectivere and its senile vulnerability of the brain to hypoxia.
Pathology International | 2001
Zean Zhang; Hiroko Nonaka; Tadashi Nagayama; Tsutomu Hatori; Fumie Ihara; Liang Zhang; Michio Akima; Tadaaki Shiba
A very rare case of a double cancer consisting of adenosquamous and hepatocellular carcinomas of the liver in a 65‐year‐old‐man is discussed. The patient was hospitalized with epigastralgia in May 1997. Abdominal computed axial tomography revealed a tumor located in the left lobe of the liver and a left hepatic lobectomy was performed. The tumor recurred several months after surgery and the patient died on 4 June 1999. At autopsy, both a major tumor mass with extensive involvement, located in the surgical margin, and a small mass located in S7 were discovered. Microscopically, the major tumor was diagnosed as adenosquamous carcinoma and the small one in S7 as hepatocellular carcinoma. To our knowledge, this is the first case of a double cancer consisting of adenosquamous and hepatocellular carcinomas of the liver. The pathological findings support the hypothesis that this tumor developed as a squamous transformation of adenocarcinoma.
International Journal of Surgical Pathology | 2007
Norihiko Saito; Tsutomu Hatori; Nozomu Murata; Kazutoshi Shibuya; Aki Mitsuda; Chikako Hasegawa; Michio Akima; Meiki Ikawa; Hiroko Nonaka
A 77-year-old woman received a total abdominal hysterectomy and bilateral salpingo-oophorectomy because of a tumor in the left ovary. The surgical specimen measured 8.5 × 4.5 × 4.0 cm, and the solid lesion measured 4.0 × 3.5 × 3.5 cm. The solid lesion was diagnosed as struma ovarii. The cyst wall partially comprised squamous epithelium-like and ciliated columnar epithelium-like cells. The tumorous lesion of the cyst wall revealed a poorly differentiated adenocarcinoma. Immunohistochemically, the tumor cells were positive for cytokeratin7, and were negative for cytokeratin20 and thyroid transcription factor-1. The authors diagnosed that struma ovarii and other parats coexisted as a poorly differentiated adenocarcinoma that had arisen from a mature ovarian cystic teratoma. As for the identification of the origin of adenocarcinomas arising from mature ovarian cystic teratomas, more cases need to be identified and investigated.
Pathology International | 1972
Michio Akima
An electron microscopic observation of the central nervous system of adult rabbits in normal and pathological conditions was performed from the view‐point of histological topography.